This invention relates to a touch panel system and a method for using the same. The touch panel can be utilized with different types of electronic information display screens such as cathode ray tubes or other types of flat panel displays.
Presently existing touch panel systems are of different types. Some systems utilize a resistive membrane, but these devices are easily scratched, and they often attenuate the light coming from the panel. These devices are also sensitive to humidity.
Another type of touch panel is the capacitive touch panel which is constructed with a durable metal oxide on a transparent substrate over the screen. This type of touch panel does not scratch as easily as the resistive membrane, but it requires a conductive probe and is not sensitive to gloved fingers or pencils.
Another type of touch panel is an acoustic panel which utilizes sound waves which are interrupted by the finger or other stylus or object. This type of panel has high resolution and doesn't attenuate light, but it has the major drawback that it is incapable of reliably detecting large objects and it is also sensitive to dirt and stray objects on the screen.
Other present touch panel devices operate on the principle of having the operator interrupt two perpendicular beams of light as the operator touches the screen. One of these devices utilizes a row of infrared LEDs on two adjacent edges of a rectangular screen with the LEDs pointing straight across toward the opposite edges of the rectangular screen. Along the two opposite edges are rows of infrared phototransistors or detectors which point straight back towards the LEDs in a one-to-one corresponding relationship. These devices require a large number of infrared emitters and detectors, and also require many electrical components for analysis of the signals.
It is therefore an object of the present invention to provide an improved touch panel system and method for using same.
A further object of the present invention is the provision of a touch panel which has fewer moving parts.
A further object of the present invention is the provision of a touch panel system which is solid state and which is reliable and rugged.
A further object of the present invention is the provision of a touch panel system which minimizes the attenuation of the display light.
A further object of the present invention is the provision of a device which can be used with all types of flat panel displays such as direct current gas discharge display panels, alternating current gas discharge display panels, liquid crystal display panels, electro-luminescence display panels, vacuum fluorescent display panels, and other types of information display panels.
A further object of the present invention is the provision of a device which minimizes the effect that ambient light can have upon the operation of the device.
A further object of the present invention is the pro vision of a touch panel system which creates an improved definition of signal for use with the display panel.
A further object of the present invention is the provision of a touch panel system which is inexpensive to manufacture, durable in use, and efficient in operation.